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J D Clarke

Publications and source records attributed to J D Clarke.

57 records · Page 4Linked to original sources

Abnormal concentrations of B vitamins and amino acids in plasma and B vitamins in bile of rabbits with aflatoxicosis.

The dosages of aflatoxin B1 (AFB1) required to produce significant changes in concentrations of B vitamins in plasma and bile and of amino acids in plasma of rabbits were determined. Folate increased by 98% in plasma, whereas concentration of thiamine, vitamin B6, and biotin decreased by more than 50%. In bile, choline and biotin increased 14- and 18-fold, respectively, whereas folate and niacin decreased by more than 50%. All amino acids in plasma increased between 76 and 155%. The dosages of AFB1 required to induce these changes were usually between 12.5 and 37.5 microgram/kg of body weight per day. Except for changes in biliary concentrations of pantothenic acid, folic acid, and biotin, lower threshold dosages of aflatoxin were required to produce weight loss and anorexia (5.0 and 8.5 microgram of AFB1/kg per day, respectively) than for changes in vitamins and amino acids (approximately 25 to 50 microgram of AFB1/kg per day). The data indicated that AFB1 interfered with the metabolism of B vitamins and amino acids in rabbits.

Aflatoxin B1↗

Effects of restricted food and water regimes on the estrous cycle of the rat.

The possibility that daily food and water presentation is a more potent synchronizer to the estrual rhythm of the female rat than the light-dark cycle was investigated by presenting food and water ad libitum only during the dark period or only during the light period of an LD 12:12. It was found that the daily feeding and drinking regimes did not synchronize the estrous cycle, but only disrupted the synchrony between the LD cycle and the estrous cycle. Because there was no significant difference between body weights of the groups, results cannot be interpreted in terms of under-nourishment effects on hormone synthesis, but rather in terms of the temporal characteristics of food and water intake.

Animals↗